Plans are afoot to make changes that would enable farmers in Manawatū-Whanganui to keep farming while working towards improving their nitrate leaching levels.

Horizons Regional Council decided in August to start looking at how it could change its One Plan – the document that governs how natural resources are managed in greater Manawatū-Whanganui.

While the majority of the plan is uncontentious, a sticking point has been nitrogen leaching limits for farmers.

After various court battles over the One Plan, the council was left in a position where many farmers, particularly horticulturalists in Horowhenua and Ruapehu and dairy farmers in Tararua, would be unable to get resource consents to operate.

At a strategy and policy committee on Tuesday, the council decided to get further advice on interim solutions.

olicy and strategy manager Tom Bowen said the most pressing issue was farmers requiring consents.

It appeared very few could meet nitrate targets set out in One Plan, which require nitrate leaching to fall to certain levels over 20 years, but there was no fallback option for those who were still going in the right direction.

Applying the targets in their strictest form would cause economic and social "disruption" well beyond what was anticipated when the plan was made, he said.

One option was to "recalibrate" the targets, which Bowen said would probably allow for higher levels of leaching in the first compliance year.

The 20-year target would stay the same, as that would help keep changes to a minimum, he said.

"We are still looking to get to the same place in the long term, but providing a more realistic path in the short term."

Another option be to simplify the targets, making it easier to get a consent, but still requiring the worst offenders to make bigger changes, faster, Bowen said.

However, both options would probably leave some farmers unable to meet targets.

Bowen said a way around that would be to issue a special kind of consent with a short expiry, as an interim measure.

The overall aim was to tweak parts of the plan, but sticking to its specific goals to improve water quality.

"If we want to get it through quickly, it needs to be uncontentious," Bowen said.

There was the possibility of more legal action, but the plan was to do everything possible to avoid that.

Council staff will also start reviewing water catchments.

Bowen said the review would take some years to complete, and would inform water policy and nutrient allocation in the long term.

But the One Plan needed to be changed sooner, rather than later, due to the existing uncertainty, he said.